We investigated the profitable fishing management of juvenile Japanese spiny lobster Panulirus japonicus, using a fisheries model and data of fishing and market records at Wagu, Mie, Japan. The predicted yields were compared among several fishing operation patterns in which fishing of juveniles in the shallow water was regulated and monthly distributions of fishing efforts were varied. The simulation showed that the yield increased when the fishing area was regulated, and that it increased moreover in spite of the constant catch number when fishing efforts were concentrated on the last months of the fishing season. It was suggested that the regulation of the fishing area together with the concentration of the fishing efforts on the last fishing period can ensure the effective utilization of juveniles.